21802116 has 48 divisors (see below), whose sum is σ = 58411136. Its totient is φ = 6200064.

The previous prime is 21802097. The next prime is 21802117. The reversal of 21802116 is 61120812.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 21802092 and 21802101.

It is not an unprimeable number, because it can be changed into a prime (21802117) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22800 + ... + 23736.

Almost surely, 2^21802116 is an apocalyptic number.

It is an amenable number.

21802116 is an abundant number, since it is smaller than the sum of its proper divisors (36609020).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21802116 is a wasteful number, since it uses less digits than its factorization.

21802116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1228 (or 1226 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 21.

The square root of 21802116 is about 4669.2736051767. The cubic root of 21802116 is about 279.3612822016.

Adding to 21802116 its reverse (61120812), we get a palindrome (82922928).

The spelling of 21802116 in words is "twenty-one million, eight hundred two thousand, one hundred sixteen".